A Real Engine in Your Browser: Alpha-Beta in 500ms
YiBoard’s Gomoku AI is not a cloud API; it is an alpha-beta pruning engine running locally in your browser with a 500ms search budget. No queue, no rate limits, available to everyone.
Most chess-style sites use a cloud API for their AI: you move, the server thinks, and at peak hours you wait in a queue. YiBoard’s Gomoku AI is the opposite: it is an alpha-beta pruning engine running locally in your browser with a 500ms search budget per move. Here is why it is fast, why it is free, and why everyone can use it.
What alpha-beta pruning is
Game search is recursive reasoning: "if I go here, where will you go, and then where do I go?" The naive version explodes into too many branches. Alpha-beta pruning records the best known result so far and cuts off branches that cannot beat it, which multiplies the search depth you can reach in the same time. Gomoku has a large board and many branches, so the pruning payoff is especially large.
Why put the engine in the browser
- Zero latency: no network round trip, the reply is instant
- Zero queue: every player searches with their own CPU, nobody waits on anyone
- Zero rate limits: play the AI for as long as you want
- Zero-cost scaling: compute follows the players, the server only referees and matches
This is the engineering foundation of "free, no signup": the cost of AI matches is spread across players’ devices instead of concentrated on our servers.
What 500ms means
Five hundred milliseconds is the search budget for one move, which feels like "the AI thought briefly and played". In that window the engine searches as deep as it can and picks a solid move. Want to meet it? Start an [AI match](/play) and see how long before you beat it.
FAQ
Will an in-browser AI lag?
No. The engine has a hard 500ms budget and always responds on time without blocking the page. Ordinary devices run it fine.
Why not a cloud AI?
A local engine has zero latency, zero queue and zero rate limits, and it spreads compute cost across player devices, which is the engineering basis of the free model.
How strong is the AI?
Within the 500ms budget it is a solid opponent for casual players. Future difficulty tiers are planned.
Does the AI cheat?
No. It follows the same placement rules, and matches against it are server-validated like human games.